JP-A-8-260400 discloses a drying mold aiming at rapidly drying a pulp molded article by efficiently supplying heat energy to the article. The drying mold has a thick mold member having a large number of vent holes, a frame member which provides a hollow chamber in the back of the thick mold member and has a compressed air feed pipe connecting to the hollow chamber, and a heating means embedded in the thick mold member.
Because the heating means of the drying mold is in the thick mold member, it is near the article to be dried. Therefore, where an article has a complicated shape, the degree of drying can vary from part to part, resulting in non-uniform drying. For example, drying can proceed excessively in some parts of an article, resulting in discoloration or scorches of pulp, while some other parts remaining wet. The number of the heating units must be increased in order to prevent non-uniform drying, which will increase the production cost of the mold.
Where articles of different shapes are to be dried, as many thick mold members as the shapes should be prepared. Having heating means embedded therein, the thick mold member is costly and has little flexibility to the shapes of articles.
In case the heating means is exchanged as the life expires, the whole thick mold member must be renewed, which is bad economy. Exchanging only the heating means with a new one requires removal of the embedded heating means from the thick mold member. That is, the thick mold member has poor maintainability.